Flotation process



Patented Jan. 8, i935 PATENT OFF-ICE.

' FLOTATION raocnss Tonten'nasselstrom, NewYork, N. Y.

No Drawing.

Application December s, 1931,

Serial No, 578,842. Renewed March 31, 1934 17 Claims. (01.209-166)Thepresent invention relates to the use of a novel flotation agent foruse in the concentration of oxidized ores containing alkaline earthmetals.

It is an object. of the present invention to employ a novel flotationagent which ,is-capable of yielding improvedrecoveries in the flotationof oxidized ores of the alkaline earth group and which is capable ofbeing utilized in a practical manner on an industrial scale withconventional flotation equipment.

It is another object of the invention to employ a flotation agent fortheconcentration of oxide alkaline. earth ores. p

It is also within the contemplation of the invention to employ aflotation agent of the character described which is cheaper than agentsnow known and available to the art and which is capable of beingobtained in largequantities from the paper and pulp industry.

4 Other objects and advantages of the present invention will becomeapparent from the ing description. v i

I have discovered that talloel obtained from black liquor of the sulfateprocess of paper and pulp making is very effective as a flotation agentfor the concentration of oxidized ores of certain metals, to wit:alkaline earth metals, and is follow- 1 capable of yielding improvedrecoveries of the valuable minerals far in excess of those obtained withflotation agents heretofore known and employed. i

Generally speaking, the present invention contemplates the utilizationof talloel in a'pulpof oxidized ores of alkaline earth metals which hasa water phase having ,a fairly pronounced alkalinity for effecting theseparation and recovery of the valuable mineral particles, termed theconcentrates, from the waste gangue, termed the tailings. I

According to the present discovery oxidized alkaline earth metal oresare subjected to the usual operations to produce a mass of ground ore.In. the event 'wet grinding has been used, the water content is adjustedto such an amount that the solids represent between about 65% to about75% of the total mass of pulp. If dry grinding has been employed, asumcient amount of water is mixed with the ground oreto producea pulpwhose solid content is about 65% to about 75%. The water phase of thepulp is rendered alkaline by the use of a reagent which has nodetrimental effect on the flotation operation and which does not form aprecipitate with the flotation agent. In practice it hasbeen found thatthe pH value of the water phase is preferably about 7.5 to about 9.0. Ofthe various alkaline reagents caustic soda is the most practical andeconomical.

Of course, other equivalent alkaline reagents,

such as sodium, potassium or ammonium carbonate, potassium or ammoniumhydroxide, sulfldes of sodium or potassium, or the like, maybe employed.g

w The aforesaid mass of pulp is thereafter mixed with talloel insumcient amounts to effect a separation of the mineral particles fromthe gangue. In practice the water is maintained at a temperature suchthat the talloel is in a liquid condition. Ordinarily, a temperature ator above about C.may be used to give satisfactory ree sults.

After thorough and complete mixing, it is preferred to effect flotationof the mineral by passing the treated pulp through a flotation cell,preferably provided with mechanical agitation and subaeration. Themineral particles are floated to the surface by the aid of the talloeland may be drawn oil? the top of the flotation cell as a frothy masswhich contains the concentrates. The gangue settles to the bottom andis'withdrawn as the tailings. Of course, the flotation and recovery ofthe mineral may be efiected in a series of cells instead of one cell asthose skilled in the art will readily understand. Inthis case, the pulpis first treated in one flotation cell to give a clean tailing but acontaminated concentrate. From the first cell, the contaminatedconcentrate is conducted to a second flotation cell where furtherquantities of gangue are separated from the valuable mineral in the formof tailings. This operation can be repeated as often as desired or untila concentrate of the desired purity, is obtained.

For a betterunderstanding of the present invention by those skilled inthe art, the following specific and illustrative examples are given.

metal is calcium phosphate which occurs in nature in various minerals.The moreimportant minerals are apatite, phosphate rock, phosphorlte,etc. which occur in Florida, Tennessee, Russia, Finland, Sweden, Norwayand French and Spanish Moroccos, and other places in the world. As thoseskilled in the art know, the crude ores may contain quartz, calciumcarbonate, oxides of iron, alumina, clay, silicates; and the like, whichare considered as impurities or contaminants.

In the case of pebble phosphate ore, such as found inFlorida, the crudeore is usually screened to separate the coarse ore from mud balls, etc.The screened ore is washed and screened again to obtain high gradeproducts and flne material, known aswasher debris. The washer debrisconsists" of particles whose'sizes are approximately minus onemillimeter. This debris constitutes the feed for the flotation processand is preferably deslimed before treatment by the flotation process.

The hard rock phosphate ores are first crushed and ground, preferably inthe presence of water,

' in size from about minus 20 or 30 mesh to about plus 200 or 300 mesh.v

The ground ore is preferably de-slimed in the ...customary manner by theuse of suitable apparatus, such as the well known Dorr bowl classifler,or the like. After the de-sliming operation, the water content of thede-slimed ore is preferably adjusted to give a pulp containing about toabout 75% of solids say about This pulp is treated with caustic soda toimpart a pronounced alkalinity thereto. In practice it is desirable tocontrol the pH value within a range from about 7.5 to about 9.0 andpreferably from about 8.0 to about 8.5. Usually it is preferred toincorporate the caustic soda in the pulp in a mixer.

After the pulpjhas been rendered alkaline with caustic soda, it j.ispreferred to add a mineral oil. Ordinarily, a petroleum oil, such asfuel oil or a twenty gravity crude oil or mixtures thereof may beemployed as the mineral oil and incorporated in the pulp by the use ofthe mixer. Instead of petroleum on, other appropriate or equivalent oilsmay be used, such as shale oil, derivatives or by-products of coal taror wood tar, or the like, may be used. It should be noted that mineraloils containing unsaturated hydrocarbons -,are preferred and give betterresults.

Talloel is finally added to the mixed pulp, preferably in such quantitythat oil floating on the surface of the mass is incorporated in the bodyof the pulp. Mixing is preferably continued until the talloel isthoroughly and completely embodied and distributed in the pulp. Whensubstantially Feed complete distribution of 'talloel is efiected, the

pulp is readyfor flotation.

The treated pulp is conducted to a flotation cell which is preferablyprovided with mechanical agitation and sub-aeration. The valuablemineral, i. e. calcium phosphate, is floated to the surface of the celland is collected as a concentrate whereas the gangue sinks to the bottomof the cell and is removed as a tailing. By de-watering and/or dryingthe concentrate, it is ready for use by itself or for use in themanufacture and production of super phosphate of lime;

Example No. 2

. Phosphate ore of the kind found in Florida and thoroughly in the pulpa petroleum fuel oil was FM added to the causticized pulp to the extentof I about 1.5 pounds of fuel oil per ton of dry feed.

Finally, talloel was incorporated in the pulp mass to an extent of about1.25 pounds of talloel per ton of dry feed. 7 1

After the addition of caustic soda, fuel oil and talloel' to the pulp,the entire mass was mixed thoroughly and completely to efiect asubstantially complete distribution of the constituents .throughout thepulp mass. The treated pulp was gangue sunk to the bottom and wasremoved at that point.

The results obtained in this example are indicated in the followingTable I. In this table, the

abbreviation B. P. L." designates bone or basic phosphate of lime as oneskilled in the art readily understands.

Table I B. P. L lvfaterial weight B. P. L. move,

Per cent Per cent Per cent Feed 100. 0 20. 79 Concentrates 27. 8 63. 5085. 0 Tailings 72. 2 4. 32 15. 0

Example N0. 3

' Pounds per ton of dry feed Caustic soda 0.5 Fuel oil 5.0 TalloeL. 1.25

The results obtained from this example are given in Table II.

Table II Materiel Weight B. P. L.

Example No. 4

Phosphate ore which has been de-slimed and which has the size of minus20 mesh was treated in accordance with the method set forth in ExampleNo. 1. The proportions of the reagents used, however, were as follows:

Pounds per ton ,ofdryfeed Causticsoda 0.50 Fuel oil I 5.0 Talloel 1.0

The results obtained in this example are set forth in the folowing TableIII:

For the purpose of comparison and for the purpose of demonstrating theimprovements over and above the art, a test was made in which a feed ofde-slimed, minus 20 mesh of phosphate ore, was used. In place of thepresent flotation agent, however, the well known red oil or oleic acidwas used. The proportions of the reagents used are as follows;

Pounds per ton of dryfeed Caustic soda 0.50 Fuel oil 5. 0

Red oil 1. 0

I The results of this example 1,980,816 The results obtained in thistest are indicated in proportions of the reagents used are as follows:

the following Table IV.v I

Table IV Material Weight B. P. L fl g-;

Per cent Per cent Per cent Fee 100.0 Concentrates l5. 8 00. l3 67. 8Taillngs 84.2 9.48 42.2

By comparing the results obtained by the use of the present flotationagent and process as shown in Table II and Table III with the results Robtained by the use of the well known red oil and the conventionalprocess shown in Table IV, it

will be clear that the present flotation agent and the process ofutilizing the same provides results which are in excess of thoseobtainable by the use of red oil and the conventional process.

In the treatment'oi phosphate or other ore, the following proportionsmay be used:

Caustic soda about 0.2 to about 2.0 lbs. per ton of dry i'eed. i

Mineral oil about 2.0 to about 10.0.lbs. per ton of dry teed.

Talloel about 0.3 to about 5.0 lbs. per ton of dry feed. r

It will be noted that the proportions of the various reagents" can becontrolled within a wide range. As one skilled in the artunderstands,the proportions may be varied with diflerent ores, sizes of iced,apparatus employed, character of water, and the like, and maybe adjustedand controlled as is customary in the flotation art to meet particularconditions.

Example No. 5

As an exampleoi a barium ore, baryte may be cited as being one amenableto the present process and flotation agent. A synthetic mixturesimulating a natural baryt'e ore was made up with river sand and crudebaryte. About of river Pounds per ton of dry i'eed Caustic soda 0.6Mineral oil 5.0 Thlloel----- 4.0

are indicated in the following Table V. I 0

Table V BaBOa Materlal Weight Ba804 new),

Per cent Per cent 43. 10 72. 13 M. 9 m. 49 39. 1

. said synthetic mixture oi baryte ore, was used.

In place of the present flotation agent, however, the well known red oilor oleic acid The Pounds per ton of dry teed Caustic soda 0.60 Fuel oil5.0 Red 11---. 4.0

Weight p so Example No. 6

Pounds per ton ot dry teed Caustic soda -0.6 Mineral oil .5.0 Talloel4.0

The results oi this example are indicated in Table VII.

Table VII SICOi Material Weight BICOI my Per cent Per cent cent 100. 036. Concentrates. so. 0 81. 26 82. l 63. l 10. 35 17. 9

For the purpose of comparison and for the purpose of demonstrating theimprovements over and above the art. a. test was made with the aforesaidsynthetic mixture oi strontianite ore. In place of the present flotationagent, however, the well known red oil or oleic' acid was used.

The results obtained in this test are indicated in the Table vm.

Table VIII v SICO: Material 7 Weight 8:00; mm

Per cent Per cent Per cent Food 1(1). 0- 42. 77 Concentrates 41. 1 Bl.82 7s. 6 Tlflln 66. 9 l5. 66 21. 4

It will be observed that the present invention provides a flotationagent and a process oi utiliz- The proportions of the reagents used areas follows:

Pounds per ton v of dry teed Caustic soda. 0.60 Fuel oil--- a 5.0 Red011-- 4.0

ing such agent whereby oxidized ores of the alkaline earth metals can beconcentrated and alkaline earth minerals can be recovered fromimpurities and contaminants satisfactorily, efficiently andeconomically.

It will also be noted that the oxidized ores of alkaline earth metalsinclude such ores as calcium obtained from black liquor of the sulfateprocess is referred to as the improved flotation agent for oxidized oresof the alkaline earth metals of the character specified herein. It is tobe noted that the black liquor of the sulfate process of paper or pulpmaking is not to be confused with liquor obtained from the sulfiteprocess of paper or pulp making or other-processes because the liquorobtained from these other'processes wfll not yield talloel which ,-iscapable of functioning as a flotation agent for the ores mentioned.herein.

In carryingthe present invention into practice it is preferable to usetalloel which has been refined. In essence, it is preferred to use atalloel which is substantially devoid of ligneous matter, of highsaturated fatty acids of sulfate black liquor and which contains reducedamounts of oxidized colophonic acids and of non-saponifiable matter. Arefined talloel of this sort has an acid number of about 190 to about200, an iodine number of about 200 to about 210 according'to the Hanusmethod and aspeciflc gravity of more than- 0.89 to less than 1.00 atabout 20 C. When crude talloel is left standing for about 2 days toabout days at atmospheric temperatures or at re- -frigeratedtemperatures, the aforesaid constitucember 3rd, 1931.

Although the present invention has been herein described in connectionwith certain specific proportions, temperatures, concentrations, and thelike, it is to be observed that variations may be resorted to as oneskilled in the art will readily understand.

. l. The process of concentrating an oxidized ore of an alkaline earthmetal which comprises forming a watery pulp of such ores, making saidwater pulp alkaline with a pH value of about 7.5 to about 9.0, agitatingsulfate black liquor talloel with the aforesaid pulp to form a frothymass of said oxidized ore and collecting said frothy mass.

2. The process of concentrating an oxidized ore of an alkaline metalwhich comprises grinding such ore to provide ground material whichvaries in size from about minus 30 mesh to about plus 300 mesh, forminga watery pulp containing about 65% to about of solids, making saidwatery pulp alkaline with a pH value of about 7.5 to about 9.0,agitating sulfate black liquor talloel with said pulp to form a frothymass of said oxidized ore and-collecting said frothy mass.

3. The process of concentrating an oxidize ore of an alkaline metalwhich comprises grinding such ore to provide ground material whichvaries in size from about minus 30 mesh to about plus 300 mesh, forminga watery pulp containing about 65% toabout 75% of solids, making saidwatery pulp alkaline with a pH value of about 7.5 to about 9.0,incorporating mineral oil in said pulp, agitating sulfate black liquortalloel with said pulp to form a frothy mass of said oxidize ore andcollecting said frothy mass.

4. The process of concentrating an oxidized ore of an alkaline metalwhich comprises grinding such ore to provide ground material whichvaries in size from about minus 30 mesh to about plus 300 mesh, forminga watery pulp containing about 65% to about 75% of solids, addingcaustic soda. to said waterypulp to make the same alkaline with a pHvalue of about 8.0 to about 8.5, incorporating a petroleum oil in saidpulp, agitating sulfate black liquor talloel with said pulp to'form afrothy mass of said oxidized ore and collecting said frothy mass.

5. The process of concentrating an oxidized ore of an alkaline metalwhich comprises grinding such ore to provide ground material whichvaries in size from about minus meshto about plus 300 mesh, forming awatery pulp containing about a frothy mass of said oxidized ore andcollecting v said frothy m'ass.

6. The process of concentrating an oxidized ore of calcium whichcomprises forming a watery pulp of such ore, making said water pulpalkaline with a pH value of about 7.5 to about 9.0, agitating sulfateblack liquor talloel with the aforesaid pulp to form a frothy mass ofsaid oxidized ore and collecting said frothy mass.

'7. The process of concentrating an oxidized ore of calcium whichcomprises grinding such ore to provide ground material which varies insize from about minus 30 mesh to about plus 300 mesh, forming a waterypulp containing about 65% to about 75% of solids, making said waterypulp alkaline with a pH value of about 7.5 to about.9.0,

65% to about. 75% of solids, adding caustic soda agitating sulfate blackliquor talloel with said 8. The process of concentrating an oxidized oreof calcium which comprises grinding such ore to provide ground materialwhich varies in size from about minus 30 mesh to about plus 300 mesh,forming a watery pulp containing about to about 75% of solids, addingcaustic soda to said watery pulp to anextent of about 0.2 to about 2.0pounds per ton of dry feed to make the same alkaline with a pH value ofabout 8.0 to about 8.5, incorporating a petroleum oil in said pulp to anextent of about 2.0 to about 10.0 pounds per ton of dry feed, agitatingsulfate black liquor talloel to an extent of about 0.3 to about 5.0pounds per ton of dry feed with said pulp. to form a frothy mass of saidoxidized ore and collecting said frothy mass.

9. The proces of concentrating an oxidized ore M i V with a pH value ofabout 7.5 to about 9.01 agitat ing sulfate black liquor talloel with theaforesaid pulp to form a frothy mass of said oxidized ore and collectingsaid frothy mass.

10. The process of concentrating an oxidized ore of strontium whichcomprises grinding such ore to provide ground material which varies insize from about minus 30 mesh to about plus 300 mesh, forming a waterypulp containing about 65% to about 75% of' solids, making said waterypulp alkaline with a pH value of about 7.5 to about 9.0, agitatingsulfate black liquor talloel with said pulp to form a frothy mass ofsaid oxi-' v a frothy mass of said oxidized ore and collecting dized oreand collecting said'frothy mass.

11. The process of concentrating an oxidized ore of strontium whichcomprises grinding such 4 ore to provide ground material which varies insize from about minus 30 mesh to about plus 300' mesh, forming a waterypulp containing about 65% to about 75% of solids, adding caustic soda tosaid watery pulp to an extent of about 0.2 to about 2.0 pounds per tonof dry feed to make the same alkaline with a pH value of about 8.0 to

about 8.5, incorporating a petroleum oil in said pulp to an extent ofabout 2.0 to about 10.0 pounds per ton of dry feed, agitating sulfateblack liquor talloel to an extent of about 0.3 to about 5.0 pounds perton of dry feed with said pulp to form a frothy mass of said oxidizedore and collecting said frothy mass.

12, The process of concentrating an oxidized ore of barium whichcomprises forming a watery pulp of such ore, making said water pulpalkaline with a pH value of about 7.5 to about 9.0, agitating sulfateblack liquor talloel with the aforesaid pulp to form a frothy mass ofsaid oxidized ore and collecting said frothy mass.

13. The process of concentrating an oxidized ore of barium whichcomprises grinding such oreto provide ground material which varies insize from about minus 30 mesh to about plus 300 mesh, forming a waterypulp containing about 65% to about 75% of solids, making said waterypulp alkaline with a pH value of about 7.5 to about 9.0, agitatingsulfate black liquor talloel with said pulp to form a frothy mass ofsaid oxidized ore and collecting said frothy mass.

14. The process of concentrating an oxidized ore of barium whichcomprises grinding such ore to provide ground material which varies insize from about minus 30 mesh to about plus 300 mesh, forming a waterypulp containing about 65% to about 75% of solids, adding caustic soda tosaid watery pulp to an extent of about 0.2 to about pounds per ton ofdry feed to make the same alkaline with a pH value of about 8.0 to about3.5, incorporating a petroleum oil in said pulp to an extent of about2.0 to about 10.0 pounds per ton of dry feed, agitating sulfate blackliquor talloel to an extent of about 0.3 to about 5.0 pounds per ton ofdry feed with said pulp to form said frothy mass.

15. The process of concentrating an oxidized ore which comprises forminga watery pulp of such ore, making said water pulp "alkaline with a pHvalue of about 7.5 to about 9.0, agitating sulfate black liquor talloelwith the aforesaid pulp to form a frothy mass of said oxidized ore andcollecting said frothy mass. 7

16. The process of concentrating an oxidized ore which comprises videground material which varies in size from about minus 30 mesh to aboutplus 300 mesh, forming a watery pulp containing about 65% to about 75%of solids, making said watery pulp alkaline with a pH value of about 7.5to about 9.0,

' agitating sulfate black liquor talloel with said pulp to form a frothymass of said oxidized ore and collecting said frothy mass.

17. The process of concentrating an oxidized ore which comprisesgrinding such ore to provide ground material which varies in size fromabout minus 30 mesh to about plus 300 mesh, forming a watery pulpcontaining about 65% to about 75% of solids, adding caustic soda to saidwatery pulp grinding such ore to proto an extent of about 0.2 to about2.0 pounds per tone of dry feed to make the same alkaline with a pHvalue of about 8.0 to about 8.5, incorporating a petroleum oil in saidpulp to an extent of about 2.0 to about 10.0 pounds per ton of dry feed,agitating sulfate blackliquor talloel to an extent of about 0.3 to about5.0 pounds per ton of dry feed with said pulp to form a frothy mass ofsaid oxidized ore and collecting said frothy mass.

TORSTEN HASSELSTROM.

